European analysts say there is no need for Russia to invade eastern Ukraine now that it has gained ultimate authority over much of the country by its takeover of Crimea and declarations of independence in the pro-Russian east.

"The referendum actually advantages Russia," Keir Giles, analyst at Chatham House's International Security and Russia and Eurasia Program London.

"They do not need to have physical control of these regions to achieve their objective for the Ukraine, which is always has been to render Ukraine ungovernable."

About 90 percent of voters allegedly backed sovereignty and two regions declared independence Monday, though the vote was impossible to confirm since it was run by the people seeking to secede. The vote in Donetsk even asked to join Russia.

Germany's foreign minister is set to visit Ukraine Tuesday to help start talks between the Ukrainian government and its foes following the declaration of independence by two eastern regions.

Frank-Walter Steinmeier hopes to encourage a quick launch of "national dialogue" between the central government and its foes in the eastern Donetsk and Luhansk regions that form the nation's industrial heartland.

Pro-Russian insurgents, who have seized government buildings and clashed with government forces during the past month, held Sunday's referendum, which was rejected by Ukraine and the West as illegal.

The European Union imposed sanctions on 13 more individuals and two businesses close to Russian President Vladimir Putin as punishment for his support for the secessionists.

Moscow has pushed for talks between Ukraine's central government and eastern regions, where nearly half the population is ethnic Russian in some regions. Putin says eastern Ukraine should be allowed autonomy from the Ukraine government, which would give him great influence in the region.

"They want to influence the political process in Ukraine, this is something that they have been demanding for some time by means of asking for an equal voice in deciding the constitutional future of Ukraine," Giles said.

Independent polls show most want better government from Kiev and do not want to join Russia. Still, Ukraine's Prime Minister Arseniy Yatsenyuk agreed to hold a dialogue with Ukraine's east on Monday as 40,000 Russian troops ready for combat remain stationed on his country's border.

The referendums follow one held in Crimea in mid-March held by pro-Russian separatists there that resulted in a Russian military invasion and annexation of the Black Sea peninsula. Many have wondered if that will be the fate of eastern Ukrainian regions. Analysts have their doubts.

"Russia annexed Crimea very quickly: We don't know if it would be the same in Donetsk at all," said Andrew Wilson, senior policy fellow at the European Council on Foreign Relations in London.

"In bigger-picture terms Russia can better control the guys in Crimea; they are real puppets. It is pretty unlikely that Russia would want to control south and eastern part of Ukraine as a whole, and it is pretty difficult to take only Donetsk."

Some analysts say if Russia ultimately accepts the move for independence, the provinces could end up as a puppet state.

"If Russia accepts the independence, we will have definitely a situation like in South Ossetia or Abkhazia or Transnistria, an independent state supported by Russia and in particular by the Russian military," said Liana Fix, an analyst specializing on the region at the German Council of Foreign Relations.

Meanwhile, Putin is pretending to lose control of the situation in the east just as he did when rebels in Donetsk kidnapped officials from the Organization for the Co-operation and Security in Europe, added Fix. That is to show he can present the face of a "good guy" to the world.

Russia has called for the international community to respect the decision of the people of the Donetsk and Luhansk regions and is calling for a "practical implementation of the outcome of the referendum in a civilized manner, without any repeat of violence and through dialogue," the Kremlin said.

But it has been largely pro-Russian separatists who for the past few weeks have stormed and occupied official buildings in eastern Ukraine, prompting the Ukrainian government to launch military operations to push them out.

"The situation is not as bad as it could yet be — it could go either way — but (it getting) even worse is more likely," Wilson said.